Scales, couplings revisited and low-energy phenomenology in M-theory on $S^1/Z_2$

Abstract. We reconsider the dimension-11 Planck scale, the physical scale of the eleventh dimension, the physical scale of the Calabi–Yau manifold and the coupling in the hidden sector in M-theory on $S^1/Z_2$. Also we discuss reasonable bounds on them. Considering the F-term of the dilaton and moduli SUSY breaking and choosing two representative points which correspond to the scalar quasi-massless scenario and the dilaton dominant SUSY breaking scenario, respectively, we analyze experimental constraints on the parameter space. The sparticle spectrum and some phenomenological predictions are also given.